Abstract

Rice blast (Pyricularia grisea) is one of the most severe diseases of rice. A Baronesse/BCD47 DH barley population was used to determine the location of the blast resistance quantitative trait loci (QTL) with different sources of blast pathogens (TH16, THL80, THL142 and THL222). Baronesse was highly resistant, whereas BCD47 was susceptible. The QTL mapped to the same linkage map position on chromosome 1H as the powdery mildew resistance locus Mla and an Expressed Sequence Tag (EST) k04320 corresponding to the barley gene 711N16.16 was obtained. Syntenic analysis corresponded to a region on rice chromosome 5. This region, including the bacterial blight resistance gene xa5, was demonstrated. These results indicated that a defined region on the short arm of the barley chromosome1H contains genes conferring quantitative resistance to multiple pathogen isolates.